Physical conditions of molecular gas in the galactic center

Makoto Nagai, Kunihiko Tanaka, Kazuhisa Kamegai, Tomoharu Oka

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

We estimated the physical conditions of molecular gas in the central molecular zone (CMZ) of the Galaxy, using our CO J = 3-2 data obtained with the Atacama Submillimeter Telescope Experiment (ASTE) in conjunction with J = 1-012CO and 13CO data previously observed with the Nobeyama Radio Observatory (NRO) 45 m telescope. The large velocity gradient (LVG) approximation was employed. The distributions of gas density, kinetic temperature, and CO column density were derived as functions of the position and the velocity for the entire coverage of the CO J = 3-2 data. We fairly determined the physical conditions for 69% of data points in the CMZ with ≥ 1 σ CO detections. The kinetic temperature was found to be roughly uniform in the CMZ, while the gas density was higher in the 120 pc star-forming ring than in the outer dust lanes. The physical conditions of high J = 3-2/J = 1-0 features are also discussed.

Original languageEnglish
Pages (from-to)25-31
Number of pages7
JournalPublications of the Astronomical Society of Japan
Volume59
Issue number1
Publication statusPublished - 2007
Externally publishedYes

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molecular gases
gas density
gas
telescopes
kinetics
observatories
dust
galaxies
stars
gradients
temperature
observatory
rings
radio
approximation
physical conditions
experiment

Keywords

  • Galaxies: nuclei
  • Galaxy: center
  • ISM: clouds
  • ISM: molecules

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Physical conditions of molecular gas in the galactic center. / Nagai, Makoto; Tanaka, Kunihiko; Kamegai, Kazuhisa; Oka, Tomoharu.

In: Publications of the Astronomical Society of Japan, Vol. 59, No. 1, 2007, p. 25-31.

Research output: Contribution to journalArticle

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